SCIENCE NOTES.

Otago Witness, Issue 2894, 1 September 1909, Page 76

SCIENCE NOTES.

— Alarm for Heated Bearings.-— A novel alarm for hot bearings consists of a small tube and bulb containing mercury, so arranged that a rise of the mercury witt temperature closes an electric ball circuit and attracts the attention of -the attendant. The apparatus »s attached to the bearing in a box 2in square. "When many bearings are being watched an ordinary electric bell indicator can be used to show which is becoming hot, and thus much trouble may be avoukdi The device is recommended for steamships and all* works having valuable machinery. j — For Bleeding at the Nose. — j The best remedy for bleeding at the nose is a vigorous motion of the jaws as if in the act of mastication. In the case of a child a wad of paper should be placed in its mouth and tne child instructed ■ to chew it hard. It is the motion of rhe jaws that stops the flow of blood. This remedy is so very simple tha« many will feel inclined to laugh at it, but it has never been known to fail, not even in very severe cases. "World of Miracles. — Herbert Spencer's prophecy that science wouk? yet become more religious than religion is fulfilling itxU, says a writer, ia the Contemporary Review. finalise but drmly^ the wonders of this stupendous cosmofc^antl the mind is overwhelmed and hatred back into dulnea* in order that jm "naj not yet burst the swaddling bands of our intellec- , tual childhood, and may continue awhile, longer on this j-udimenia» plane. But many of us are too dull to realise even «Kn\ly the miracles which surround us or those we carry about with us. .! — Magnetism Incrta&ss Strength of Iron and Steel.— That magnetism affects the strength of iron and steel seems to have-b een proved by Mt W. J. Crawford, at the Technical Institute of Belfast, Ireland. He used bare j of mild steel and wrought iron Bin long by ; three-fifths to lin in diameter, part of them t being kept at magnetic saturation in a solenoid, and & the testing machine the elongation of the magnetised pieces was de- , creased 5 to 16 per cent., while the average breaking load seemed •■to be increased. — Automatic Telephone. — An automatic telephone exchange system is in use in Vienna, and has been -tested for j a number of years. As a result of these tests the head of the Austrian telegraphs, Mr Charles Barth de Wehrenalp, declares j that the automatic system can be made to ■ seriously compete with Abe manual system. 1 He states that in New York it takes on. the average 16 seconds £rpm the time the sub- j ecriber removes his telephone receiver to the i time the ringing signaJ is set; whereas in j the automatic system for 100,000 subscribers this •work is done in but 10 seconds. Three seconds after' the subscriber hangs up the i receiver the line is clear. Owing to this . ' saving in time a larger number oiv messages^ .^can be delivered through the automatic ex- „ change than through the manual exchange, r — The Easiness of Death.— J " - _- Dr E. L. Keyes, in a paper in Harpea-*e t . makes this statement :~"Ifc is j 2«s natural to die as it Is'io live—^and, as' - easy. Practically -all the distress witnessed ' as taking piece in Ihe act of dying is the automatic tissue struggle against dissolution, and is not recognised by the individual who ieenis to be acutely suffering. Occasionally in the delirium of fever, in uremia and other intoxications, in- certain of the brain degenerations witnessed in old age, there is an exhilaration or happy peaceful calm that pervades the final scene." It has been' sometimes stated that certain people die in "conscious terror and protest." Dr Keyes j has neve? seen a case of this .kind. In nearly all the many scores of deaths that • he has witnessed the main actor at the last j moment was not conscious of what was going on. - —Can Life be Bekindied?— Life is continuous from one generation to the next, but late observations have shown |,ts resumption after being apparently brought to a complete stop. Professor Paul Becquerel has -been making experiments with grains of wheat and- mustard. These he has dried bj a special process for sir months, then sealed in a high vacuum for one year, and finally cooled *n liquid air 'or three weeks, and at 253deg below xero C. for 77 hours. Without water and air, add* an a temperature near absolute zero, the protoplasm becomes as rigid, hard, and inert as «tone. " Profeeso* '^Becquerel believed that under such conditions the vital functions mus* be entirely suspended, yet when sown afterwards the seeds grew as usual, and this i* thought to disprove the long-accepted lew lhat the least, interruption of lifo must be death. Whether the apparent stoppage of life may continue indefinitely is a subject for further experiment — Concrete Railway Sleepers. — The earthquake- resisting qualities of reinforced concrete have received a demonstration, in Messina, where, we are told, buildings constructed of this material remained uninjured, even :n: n those parts of the city which were most severely visited by the earthquake. A dwelling built of reinforced cocrete was the only • building j left standing, and its occupants were j sole survivors of a large section which was \ reduced to ruins. The reservoir of rein- I forced concrete ;was entirely uninjured, and j -the water 6upply was not interrupted for an instant. Several German railway lines have been using reinforced .xm- j crete cross-sleepers for upwards of four | years, and the results have been entirely | satisfactory. The sleepers are 7.2 ft long, j weigh 3081b, and cost about 6s each. This great weight lends stability, the rails fastenings are very secure, and there is but little wear caused. They promise to have a much longer life than wooden sleepers, and are considered by a great many to possess advantages over the much-]6oked-to metal deeper. — The Energy of Radktm. — ■ Professor Sir ,J. J. Thomson, of Cambridge, in a lecture on -the "Properties of Matter," at the Roya! Institution, observed that the theory of .the structure of atoms and molecules, the old units of physics and chemistry, had been placed on a new Tooting by the discovery of rad£o-a<etive sub■tanes. From the -atoms of radium, most potent of these elements, energy was given out exceeding anything with which men of ■cience bad previously been acquainted. P\*dium, in g» breaking up, si fitted a mil-

I lion times as much energy ■• as was pro- | duced by the combination of equal weight !of oxygen and hydrogen. It threw' off corpuscles or atoms of helium, moving with one-tenth the velocity of light — or about 18,000 miles per second. Whence came this amazing amount of power was a most interesting Question The condition of a ship exposed to the fire of a Dreadnought would be child's play compared with the condition of an atom exposed to a battery of these particles. If they imagined a town exposed to a bombardment of o'iof's as large as houses, and moving a thousand times more quickly than any missiles ever shot out of a canon, they would have s*re idea of the condition of a gas exposed to the bombardment of radium. j — Electricity and the Farm. — ; There is great scarcity of labour in the agricultural districts of Fiance on account of emigration to the cities, but at the Marseilles Electrical Exposition it is shown how electricity can be made to perform all the arduous work on the farm, thus replacing human labour. The modernised farm, which covers a surface of 12,000 square feet, ie on« of the moss interesting attractions at the exposition. AH rive buildings of a typical farm are reproduced. The dwelling is equipped electrically throughout ; th^ra is an eketrical cooking . stove an the kitchen, an electric pump supplying mnieed water, an electric pump bread-kueader, and The. lauctiry is furnished with a special pump, electric wash machine^and irons. In the yard* are a centrifugal pump installed over a well and driven by a small' motor, ploughs, threshing aia'chines, huskers, winnowers, etc/ The wine cellar has a wine "pump, ' grape-picker, bsa>tar, and press— all operated electrically. In the poultry- house there are a bone-oriishei'. herb-cutter, electric brooders and bree^&rs. The cow-house contains t lerrot-cufcter. grain-crusher, oilcake mill, root-cutter, apparatus for milking cows. The dairy is furnished with cream separators, beaters, and churns. A pump and ice-making machine complete the outfit. In ihe stable an. electric straw-cutter has been installed, and alao electric shears for shearing sheep. A shop containing a forge with an electric blower, an eleotrioally-driven handsaw, grindstone, "and other tools complete the installation of the farm. — Smokeless Battleships. — : The possibility of the adoption of internal combustion engines for the propulsien of battleships has been discussed- prcand con for the past two years by navai experts. Now, however, the internal combustion engine for such purposes has ceased to be a possibility and 'has become a fact. Experiments in Britain, it is claimed, have been so successful that a hug© battleship 54-Oftr long, SBft broad, -and having a displacement of 21,000 tons, has been designed, and will scor bs laid down, ;f,; f, indeed, the work has not already been secretly commenced. If the reports are correct the vessel is designed for a speed of 29 miles an hour, and will carry an armament of 12 - guns of 13.5 in calibre, firing projectiles of 15001b weighty 'capable of piercing 32 inches of armour at "a distance of -9000 ft. The advan-iage? of thu internal lombustion engine over steam-power are numerous. There will be no smoke to draw the attention of the enemy, no funnels to obstruct •the decks, the engines will be .better protected, and oil tanks' for- fuel purposes will . be easier filled both at sea aiSd in harbour than bunkers with coal. It is the absence -of funnels, howeverj that will cause the most radical change in the exterior appearance of the war dogs. Except for masts, bridges, and conning towers the decks will be practically clear, making possible the ' arranging of big guns for firing in any : direction. The huge funnels now in use offer fine targets to the enemy : their injury may reduce the draught, and so the speed of the vessel, and their fall would probably put several guns out of action. — Electricity in Agriculture. — The science of applying electricity to plants upon a large scale to stimulate their irrowtb has received a decided impetus from the refont experiments of Sir Oliver Ledge, F.R S., at the Bitton nurseries of Mt <T. E. Newman. It may be remembered that the late Mi Thwa.ite carried out some investigations in thi? direction at tlie glasshouses of the Royal Botanical Society ir London. The Gloucester investigations, howevei, were carried out upon a far more comprehensive basis. Fields of corn, strawberries, and other produce were treated. A network of electric wire* was distributed over the field*, strung on posts disposed one to about every acre, and just—high enough to afford sufficient clearance to waggons with produce be- . ncath. Current was furnished r rom a small , oil engine and dynamo, and transformed up to a pressure of about 100,000 volts. The , negative wire is taken direct to earth, and the positive to the overhead wire network. A tremendous leakage results, which pro- , duces a stimulating effect upon the growth ' of .the crops beneath. The current is sup- J plied in accordance with a determined plan. In the 1806 season current was furnished < for 621.75 hours spread over 90 days. The effect of electrification was an increase of 30 and 4C per cent, respectively in the yield from the plots so tr-cated in com- ■ parifion with another field where, although precise!} the same conditions prevailed, '< electrification was not resorted to. In 1907 current, was supplied for 1014 hours on 115 days, the increase in yield again being 29 per cent, as compared with the unelectrincd ' field, the crop repr-3«n.ting 41.4 and 32 bushels per acre respoctholy. The electrified wheat was found to be brighter, and, moreover, realised prices some 7g per cent. higher than tbo ordinary corn, several millers in baking; tests finding that it produced a better flour. The beneficial effects secured in regard to other product* were equally striking, the augmentation iv the ease of mangolds being estimated at 25 per , cent., witli a corresponding inoreasp in the sugar. Raspberries, -tomatoes, and straw- : berries showed equal improvement under the influence of the current. The experiments are to be continued, and from the results so far obtained it i 6 obvious that the utilisation of electrical propagation upon an extensive scale offers a ready means to the farmer for the increase of the yield from his land. It opens up new possibilities in farming, and once the fact is sufficiently appreciated we may look for the design and supply of inexpensive and ; substantially-built electrical plants suitable for this industry.

WOLFE'S SCHNAPPS i The purest tonic and stimulant.